With the appearance of mass recording media such as a DVD, by reproducing, using a reproducing apparatus such as a DVD player, a recording medium in which content such as video and music are recorded, it has become possible to enjoy video and music for a long period of time. However, from the standpoint of copyright protection, it is necessary to restrict actions to copy the above mentioned content, as digital data, into other recording media such as a CD-R.
Conventionally, as a technique regarding the above mentioned copy control of content, various methods have been suggested (for example, “Record Reproducing System” as disclosed in Japanese Laid-Open publication No. 2001-125833, and the like).
In the above mentioned conventional record reproducing system, when content is recorded in a recording medium, identification information which identifies whether the content is a copied record from a mass recording medium or a moving record is also recorded. When reproducing, according to the identification information, copy permission is judged, and copying the content and the like are properly permitted or prohibited. Also, based on copy permission number, content copying is monitored, and copying up to a certain number of times is permitted.
However, in the above mentioned conventional record reproducing system, when copying content, the method for reading out, only once, and judging the identification information indicating whether the content is a copied record or the moving record is used. Thus, it cannot be said that a sufficiently secure copy control is executed. For example, when the identification information is read out from the recording medium, in the case where the identification information is captured on the transmission path, and replaced with other information, the copy control becomes invalid. In other words, there is a problem that if the important copy control information indicating copy limitation is modified once, copying becomes possible with the unit of content or recording medium.
Moreover, in the above mentioned conventional record reproducing system, the copy control is executed based on the copy permission number. However, there is a problem that since the case where the content transmission is interrupted and the like are not taken into account, the copy number control is incomplete. For example, in the case where the copy number is counted in the head part of copying, one copy is counted even if a complete copy is not finished. Thus, the user suffers the disadvantage. On the contrary, in the case where the copy number is counted in the end of copying, even if the copy is almost completed, one copy is not counted. Thus, unauthorized copying can be repeated.